DESCRIPTION OF REQUEST:

Dr. Mace requested a Groundwater Availability Model (GAM) run to evaluate the impact of an additional 4,000 acre-feet per year of pumpage from a single cell near Jewett, Texas, located in northwestern Leon County (Figure 1). This request was made to evaluate the potential of the Carrizo-Wilcox aquifer to supply groundwater to a proposed FutureGen power plant, which will be located in or adjacent to the Jewett coal mine (Figure 1). METHODS: To determine the impact of an additional 4,000 acre-feet per year of pumpage on water levels in the Jewett area, we used the GAM for the central portion of the Queen City, Sparta, and Carrizo-Wilcox aquifers. We used the 1999 estimated pumpage from the transient calibration-verification model run as the baseline pumpage for the model run. To this baseline pumpage we added 4,000 acre-feet per year to a single cell west of Jewett. A single cell was used because of the desired size of a well field for the proposed site. The additional pumpage was evenly divided between two units for the predictive model run; the Upper Wilcox (Calvert Bluff) and Middle Wilcox (Simsboro). The Uppe